Patent Literatures 1 to 4 disclose a redox flow battery including, as a main element, a battery cell including a positive electrode to which a positive electrolyte is supplied, a negative electrode to which a negative electrolyte is supplied, and a membrane disposed between the positive electrode and the negative electrode; the redox flow battery being configured to be charged and discharged while the electrolytes for the electrodes are supplied to the electrodes. The battery cell has a configuration in which a stack body of the positive electrode, the membrane, and the negative electrode is sandwiched between a pair of cell frames. Such a cell frame includes a bipolar plate on the front and back surfaces of which the positive electrode and the negative electrode are individually disposed, and a resin frame body disposed on the outer peripheral portion of the bipolar plate.
Patent Literatures 1 to 4 disclose a bipolar plate including plural groove portions through which electrolytes flow, in order to sufficiently distribute the electrolytes to the electrodes within the battery cell.